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When can the Planck satellite measure spectral index running?

Cédric Pahud·Andrew R. Liddle·Pia Mukherjee·David Parkinson
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Abstract

We use model selection forecasting to assess the ability of the Planck satellite to make a positive detection of spectral index running. We simulate Planck data for a range of assumed cosmological parameter values, and carry out a three-way Bayesian model comparison of a Harrison-Zel'dovich model, a power-law model, and a model including running. We find that Planck will be able to strongly support running only if its true value satisfies |dn/d ln k| > 0.02.

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Cédric Pahud, Andrew R. Liddle, Pia Mukherjee, David Parkinson. 2007-09-04. When can the Planck satellite measure spectral index running?. https://doi.org/10.1111/j.1365-2966.2007.12310.x

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